1. Field of Invention
The present invention relates to a solar cell material. More particularly, the present invention relates to a photosensitizer dye applicable in a dye-sensitized solar cell.
2. Description of Related Art
Along with the development of technology and economy, the use of energy (such as oil (petroleum), natural gas, coal and etc.) has caused pollution which leads to serious damages to the environment. Further, the supply of these polluting energies is coming to a close and the looming shortage of energy is a serious world-wide problem. Accordingly, many nations have started to develop and invest in cleaner and renewable energy sources.
Since solar energy is an unlimited and non-polluting energy source, it has been proposed and used as an alternative to the fossil fuels based energy to resolve the problems of pollution and energy shortage. Solar cell (or photovoltaic) which can convert solar energy directly into electricity is under intensive study.
Recently, Grätzel and O'Regan have proposed a new type of solar cell known as dye-sensitized solar cell (DSSC), which offers the prospect of an effective use of solar energy, and thus draws the attention of researchers from both academia and industry. Typically a dye-sensitized solar cell is constituted with four parts including an anode/cathode for providing a channel of current flow, a metal oxide (generally TiO2) semiconductor for accepting and transporting electrons, a photosensitizer, and an electrolyte for transporting holes. The materials and the junctions of the four parts in the dye-sensitized solar cell play important roles on the efficiency of the cell. Most particularly, the photosensitizer (or dye) is critical in determining the efficiency of the dye-sensitized solar cell. Accordingly, it is essential to identify a dye that can provide good efficiency of the dye-sensitized solar cell. It is well known that having high absorption coefficient is one of the most important parameters for being a good photosensitizer.